2, 3, 5. Trial , experiment , test imply an attempt to find out something or to find out about something. Trial is the general word for a trying of anything: articles sent for ten days' free trial. Experiment is a trial conducted to prove or illustrate the truth or validity of something, or an attempt to discover something new: an experiment in organic chemistry. Test is a more specific word, referring to a trial under approved and fixed conditions, or a final and decisive trial as a conclusion of past experiments: a test of a new type of airplane. 7. See affliction.

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